EvalModuleCallArguments is now a method on nodeModuleVariable, it's only
caller, and the other functions have been replaces with straight through
code (or in the case of evalVariableValidations, a standalone function).
I was unable to add tests for nodeModuleVariable.Execute, which requires
fixtures that aren't part of the MockEvalContext (a scope.evalContext is
one); it's not ideal but that function should be well covered by the
context tests so I chose to leave it as-is.
Finally, I removed the unused function hclTypeName. Deleting code is
fun!
While we don't have any expansion info during validation, we can try to
evaluate variable expressions to catch some basic errors. Do this by
creating module instance RepetitionData with unknown values. This
unfortunately will still miss the incorrect usage of count/each values,
but that would require the module call's each mode, which is not
available at this time.
The variable nodes are not only used during plan and apply, so remove
those from there names. The "plan" node is now
`nodeExpandModuleVariable` and the "apply" node is now just
`nodeModuleVariable`.
Remove unnecessary methods, as the nodeModuleVariable is no longer used
in the full graph transformations.
GraphNodeModulePath is similar to GraphNodeSubPath, except that it
returns an addrs.Module rather than an addrs.ModuleInstance. This is
used by the ReferenceTransformer to connect references, when modules may
not yet be expanded.
Because references only exist within the scope of a module, we can
connect everything knowing only the module path. If the reference is to
an expanded module instance output, we can still properly order the
reference because we'll wait for the entire module to complete
evaluation.
The existing "type" argument allows specifying a type constraint that
allows for some basic validation, but often there are more constraints on
a variable value than just its type.
This new feature (requiring an experiment opt-in for now, while we refine
it) allows specifying arbitrary validation rules for any variable which
can then cause custom error messages to be returned when a caller provides
an inappropriate value.
variable "example" {
validation {
condition = var.example != "nope"
error_message = "Example value must not be \"nope\"."
}
}
The core parts of this are designed to do as little new work as possible
when no validations are specified, and thus the main new checking codepath
here can therefore only run when the experiment is enabled in order to
permit having validations.
Due to how deeply the configuration types go into Terraform Core, there
isn't a great way to switch out to HCL2 gradually. As a consequence, this
huge commit gets us from the old state to a _compilable_ new state, but
does not yet attempt to fix any tests and has a number of known missing
parts and bugs. We will continue to iterate on this in forthcoming
commits, heading back towards passing tests and making Terraform
fully-functional again.
The three main goals here are:
- Use the configuration models from the "configs" package instead of the
older models in the "config" package, which is now deprecated and
preserved only to help us write our migration tool.
- Do expression inspection and evaluation using the functionality of the
new "lang" package, instead of the Interpolator type and related
functionality in the main "terraform" package.
- Represent addresses of various objects using types in the addrs package,
rather than hand-constructed strings. This is not critical to support
the above, but was a big help during the implementation of these other
points since it made it much more explicit what kind of address is
expected in each context.
Since our new packages are built to accommodate some future planned
features that are not yet implemented (e.g. the "for_each" argument on
resources, "count"/"for_each" on modules), and since there's still a fair
amount of functionality still using old-style APIs, there is a moderate
amount of shimming here to connect new assumptions with old, hopefully in
a way that makes it easier to find and eliminate these shims later.
I apologize in advance to the person who inevitably just found this huge
commit while spelunking through the commit history.
Kristin Laemmert